Ontology-Based Digital Twin Framework Using Contextual Affordances for Worker Assistance in Smart Factories

In modern smart factories we have multiple entities that interact with one another, such as worker-assistance system, robot collaboration and their corresponding software modules. To facilitate seamless cooperation between those subsystems, we propose an Ontology-based Digital Twin that allows semantic representation of all important parts of such a scenario. We extended our Ontology-based Digital Twin to be able to provide information about the object-related contextual affordances tailored to the needs of factory worker at a particular situation. We demonstrate the use of contextual affordances in a scenario using a Augmented Reality (AR) application that uses an assembly process model, where each process step carried out by the worker is taken into consideration. This illustrative AR assistance aims to guide workers. Furthermore, we evaluate the usefulness of this affordance-based assembly assistance system prototype with user test.